DL/T 459-2017 in English

Standard Revision Background and Technological Evolution

DL/T 459-2017 is a comprehensive upgrade of the 2000 version of the standard, primarily responding to the need for intelligent power system development and improved equipment reliability. The standard's title has been changed from "Technical Conditions for Ordering DC Power Supply Cabinets for Power Systems" to "DC Power Supply Equipment for Electric Power," reflecting a shift in understanding from single cabinets to systemic equipment.

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Comparison of key technical requirements

Technical indicators	2000 version requirements	2017 version requirements	Explanation of changes
AC input voltage range	±10%	-15%~+20%	Relaxed to adapt to grid fluctuations
Electrical clearance (300V)	8mm	10mm	Improve insulation safety
Electromagnetic compatibility test	2 items	4 items	New electrical fast transient and surge tests
Battery capacity test	1 cycle	3 cycles	Strict verification standards

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Technical requirements for core equipment

1. Charging device

High-frequency switching module must meet the following requirements:

• Voltage regulation accuracy ≤±0.5% (Class I)
• Current imbalance ≤±5%
• Soft start time 3-8 seconds

Typical application case: A 500kV substation uses a 400A high-frequency charging module, with a measured ripple factor of 0.3%, which meets the standard limit of 0.5%.

2. Battery pack

Valve-regulated sealed lead-acid batteries need to pass:

• 10h rate capacity test (meet the standard after the third cycle)
• 1h accident discharge + impulse discharge test
• Termination voltage adjusted to 1.8V/cell (originally 2V)

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Improved electromagnetic compatibility

Two new key tests are added:

1. Electrical fast transient/burst immunity: 2000V/5kHz applied for 1 minute
2. Surge immunity: 2000V line-to-ground impact test

Test data from a manufacturer shows that the interference voltage is reduced by 40dB after the installation of a magnetic ring, which is better than the standard limit.

Implementation Suggestions